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Figure 4.16. Travel rate cumulative distribution functions (TR-CDFs) for I-210 weather. 4.6 Assess the Contributions of the Factors (AE2) Assessing the contributions of the factors involved all of the steps for AE1 as well as the added step of developing a rank order on the facilities based on the relative impacts. This required summing the total semi-variances (SV) for each nonrecurring event category by congestion type for both facilities. Table 4.4 shows the results of this calculation. Table 4.4. Semi-Variances for Each Regime on the I-5 and I-210 Facilities Co Rte Regime Normal Demand Weather Special Event Incident Regime Total SV Facilit y Total SV n SV n SV n SV n SV n Los Angeles I-210 Uncong 177 36,624 182 3,526 223 9,184 n/a 1,428 794 10,293,632 97,249,460 Low Cong 601 8,319 147 26 689 1,978 2,610 470 7,595,685 Mod Cong 4,692 3,560 711 25 4,387 1,012 5,146 925 25,919,625 High Cong 9,744 3,454 1,585 48 8,437 1,012 11,082 1,008 53,440,518 Orange I-5 Uncong 60 37,758 94 706 199 8,600 750 1,475 667 1,661 6,255,508 97,787,935 Low Cong 1,115 7,647 2,305 8 2,495 1,849 4,145 342 2,752 947 17,186,411 Mod Cong 3,847 3,286 1,183 6 5,723 946 7,808 439 5,996 845 26,555,908 High Cong 7,780 3,546 1,465 11 12,091 946 9,958 121 8,401 898 47,790,108 0% 5% 10% 15% 20% 25% 30% 35% 40% 45% 50% 55% 60% 65% 70% 75% 80% 85% 90% 95% 100% 45 55 65 75 85 95 105 115 125 135 145 155 165 175 185 195 205 215 225 235 245 255 265 275 285 295 Cu m ul at iv e Di st rib ut io n of T rip s Travel Rate (seconds per mile) Normal-Uncong Normal-Low Cong Normal-Mod Cong Normal-High Cong Weather-Uncong Weather-Low Cong Weather-Mod Cong Weather-High Cong 68
From the Facility Total column at the far right of the table, one can see that both facilities appear to have similar levels of unreliability as measured by semi-variance. As can be expected, the higher the congestion level, the more unreliable the facility becomes, with the Los Angeles I- 210 facility being slight more unreliable. Table 4.5 shows the percent contribution of each regime. Similar to what was observed in the L02 guide, the highest unreliability on the facilities comes under highly congested time periods with normal demands (35 percent for the I-210 facility and 28 percent for the I-5 facility). On the I-210 facility, incidents and weather provide approximately the same contribution to unreliability (at 19 and 17 percent respectively). I-5 presents a slightly different story with weather exhibiting a slightly higher impact on nonrecurrent congestion at 24 percent and incidents contributing only 17 percent. Table 4.5. Percentages for Semi-Variances for Each Regime the I-5 and I-210 Facilities County Route Regime Normal Demand Weather Special Event Incident Regime Total SV Facility Total Los Angeles I-210 Uncong 7% 1% 2% 1% 11% 100% Low Cong 5% 0% 1% 1% 8% Mod Cong 17% 0% 5% 5% 27% High Cong 35% 0% 9% 11% 55% I-210 Totals 64% 1% 17% 0% 19% 100% Orange I-5 Uncong 2% 0% 2% 1% 1% 6% 100% Low Cong 9% 0% 5% 1% 3% 18% Mod Cong 13% 0% 6% 4% 5% 27% High Cong 28% 0% 12% 1% 8% 49% I-5 Totals 52% 0% 24% 7% 17% 100% 69
